Downwind faster as the wind, selfaccelerating runner

[TechStuf]

Coanda effect/inertial gain.


An astute supposition......


TS

[Super God]

Attach a small ac motor to the wheels and use it in reverse.  See how much power we can extract while still maintaining a forward net thrust.

[AbbaRue]

I was studying this device for a while as it ran on the treadmill, and I noticed an important point.
While it's running on the treadmill there is no wind friction coming at it from the front.
If it were running down the street at 10 mph with a back wind of 8 mph it would encounter 2 mph of air friction from the front.
The faster it moved the more front wind friction it would encounter.
So based on this I wonder if it would keep going if it was say fastened to a center post and allowed to circle the post.
The treadmill is deceiving because the machine runs faster then the treadmill which is moving 8 mph.
But the machine isn't encountering 8 mph air friction coming at it.
If you had a fan in front of it blowing at 8 mph the machine would go backwards not forwards.

I hope I got my point across, I know what I'm trying to say but just can't seem to find the right wording.

[Pirate88179]

@ AbbaRue:

You got your point across very well and I agree with you.  I didn't think of that but you are exactly correct.  The treadmill give the wheels the rpms they need without the penalty of any headwind due to forward motion.  It kind of negates part of the equation.  Good observation.

Bill

[AbbaRue]

Of course this doesn't explain what is happening with the unit that is actually running down the street and accelerating.
But a steady wind is rare so the wind could be speeding up and slowing down.